Shading-machine



W. H. MARGETTS.

SHADING MACHINE.

APPLICATION FILED JUNE 4. 1919.

Patented Aug. 3, 1920.

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UNITED STATES PATENT OFFICE.

WILLIAM HENRY MARGETTS, OF TORONTO, ONTARIO, CANADA.

SHADING-MAGHINE.

Application filed June 4, 1919.

To all whom it may concern.-

Be it known that I, WILLIAM HENRY MAR- cmns, a subject of the King of Great Britain, of the city of Toronto, county of York, Province of Ontario, Canada have invented certain new and useful Improvements in Shading-Machines, of which the following is a specification.

My invention relates to improvements in shading machines, and relates more particularly to the class of shading machine used in connection with lithographing, zincology, and photoengraving, and the objects of my invention are: first, to dispense with all springs or other elastic elements in the adjusting operations of the machine so as to insure absolute accuracy and ease of adjustment; second, to improve the construction so as to require only one adjustment in either directlon when adjusting the film frame transversely ofiihc boarder stone; third, to adj ustably mount the machine on a supporting member whereby it may be coupled to a drawing board, as well as to a table, supporting the stone, and whereby the height of the machine may be adjusted according to the thickness of the stone; fourth, to mount the machine on its supporting member so that it may be bodily shifted transversely of the drawing board or stone, and locked in the desired position, and fifth, to provide means for coupling the film frame to the machine so that notwithstanding the depth of the frame, the same may bepositioned to rest flat on the board or stone.

In the following part of the specification, I shall describe my preferred form of construction, and what I claim as new will be pointed out in the claims forming part of this specification.

Figure 1 is a plan view of the shading machine and its supporting member, and clamping plates therefor, showing the same attached to portion of a drawing board and carrying portion of a film frame. Figs; 2 and 3 are vertical cross sections on the lines 22, 3-3, respectively, Fig. 1, on an en'- larged scale. Fig. 4 is a side elevation of one end of the transverse adjusting means for the fihn frame. Fig. 5 is a vertical cross section .the line 5- 5, Fig. 1. Fig. 6 is an end elevation of the clamping plates and supporting member therefor, 'shcwin how the machine may be coupled at the csired height to a table above .a stone, and Fig.

Specification of Letters Patent.

Patented Aug. 3, 1920.

Serial No. 301.685.

7 is a plan view of portion of the coupling clamp for the film frame showing how the same is pivoted to the machine.

In the drawings, like characters of reference refer to the same parts. i

In prior machines of this class that I am acquainted with, springs are used in certain adjustments, but since no two springs exert the same power under all conditions, ease and accuracy of adjustment are frequently impaired. Now in adjusting the film frame by my machine, both longitudinally and transversely, I dispense absolutely with any springs, and the consequence is that greater accuracy of adjustment can be secured with consequent improvement in character of work done by the artist. I omit all keys for the purpose of securng adjustment, and since the movement of one element only is necessary to secure transverse adjustment of the film frame in either direction, I absolutely overcome defects inherent in some classes of machines in makingiadjustments of this kind.

roadly considered, the machine comprises front and rear plates; the rear plate being removabl cou led to a su port, means being associate wit said machine at each end of said plates whereby these plates are separated or moved together thereby giving the necessary longitudinal adjustment to the film frame. A threaded adjusting rod is carried by the front plate and dominates the action of a plate mounted to move longitudinally of said front plate, and which is coupled to the film frame. When the machine is embodied in the form illustrated, it is mounted on a supporting member which extends transversely across the drawing board or the stone, and clamping elements are carried by said supporting member whereby the machine is firmly coupled to the drawing board or coupled to a table and supported at the required height above the stone.

When the machine and its supporting members are used with a drawing board, certain means for adjusting the height of the machine above the top of the stone are omitted.

A is the back plate and B the front plate. Secured to each end of the back plate A by any suitable means such as screws C are internally-threaded osts D, which project above said plate. E is the movable supporting member to which the machine is coupled by any suitable means such as a thumb screw F which screws through the hole a, formed in the back plate A, and into the movable supporting member E. A plurality of holes I; are formed. in the member E so that the thumb screw l may he placed therein and secure the machine in the position it may he moved into lon itudinally of the member E. The screws (1 or other fastening means for the posts D are provided with rounded heads (l which extend into a groove ll formed longitudinally of the movable supporting member E. The back plate A is provided with a downwardly depending flange I which overlaps the rear side of the movable supporting member E. The flange I, together with the heads (i renting in the. groove H, permit the machine to be shifted longitudinally on the movable supporting member E readily upon occasion and maintain the machine at ri ht angles to the sides of the drawing board 1, E for ewample lVh le the construction justdescribed is very convenient, it is not absolutely essential. Threaded through each of the posts D is an adjusting screw 2. The forward end of each of the screws 2 is reduced as shown at 3, and is without a thread so as to have hearing in its associated post 4. These posts are coupled by any suitable means such as screws 5 to the plate B. The reduced end of each of the screws 2 projecting beyond the front side of the screws 4 is threaded and receives a circular nut 6, and a lock nut 7. Mounted on each of the posts 2 is an element, such as a nut, which is keyed to the sa' l posts by any suitable means such as a pin 9. Through the (o-action of the parts just described, the screws 2 can turn freely in the posts 4 and since these screws are threaded through the posts D by turning the same, the plates A and B may be separated and drawn together the required amount. It will be observed particularly upon referring to Fig. 2, that the circular nuts 6 are provided with a. suitable graduated scale bearing appropriate marl-tings. For example, each nut may be marked from zero up to nine. The top side of each post 4 is scored as shown at 7. These scored markings are placed directly above the longitudinal axis of each adjusting screw 2 so that the graduated scale before referred to may be accurately used so as to secure the desired adjustment at each end of the machine.

8' is an adjusting rod journaled near one end in'a plain bearing formed in a bearing block 9'. The other end of the adjusting rod is threaded and operates through a threaded hole (shown by dotted lines in Fig. 1) formed in the bearing block 10. These bearing blocks are secured firmly to the front plate B by any suitable means such as screws 11 extending through lugs 12 forming part of said bearing blocks. The nuts 13 eo-act with the said screws to firmly sup port said bearing blocks to said front hearing.

14 is a plate extending longitudinally of the front plate 13 and provided at each end with a flange 15 through which extends the adjusting rod 8. Keyed to each end of thc rod 8' and adjacent the outer side of each of the flanges 15 is a nut 16. One of the said nuts is provided with a suitable graduated scale of the character before set forth, so that the film frame 1'? (coupled to the adjusting rod. 8" by any suitable means, the preferred construction of which will be hereinafter set forth) may be shifted trans j versely of the drawing board J in either direction. One of the flanges '15 is provided at its top with a scored mark c positioned directly above the longitudinal axis of th adjusting rod 8 so that the graduated scale carried by one of: the nuts 16 may be used to secure accuracy of adjustment. It will be observed from the construction described of the adjusting rod 8 and the manner in whichthe same is coupled to the plate ll ,u

that the said adjusting rod is positively locked against longitudinal movement in the plate 14 while at the same time complete freedom of action is secured to provide for transverse adjustment of the film frame 17 in either direction.

Upon referring particularly to Figs. and 4, it will be observed that a certain portion of the bearing blocks 9 and 10, and the lugs 18 carried thereby have clearance with the plate 14 as shown at 19 thus preventing friction between these elements. In order to prevent any possibility of the plate 14 springing, l preferably mount in each lug 18 a set screw 20, the lower end of which rests easily in a groove 21 formed longitudinally in the plate 14. The friction between the said screws 20 and the plate 14 does not interfere materially with the operation of the rod 8, while this construction or its equivalent possesses the advantage of always maintaining the plate 14 with its front edge in alinement with the front edge of the front plate B in case there should be any tendency for the plate 14 to get out of alinement through the wearing of the bearings of the adjusting rod 8 in the bearing blocks 9' and 10. The holes (not shown) formed in the flanges 15 through which the adjusting rod 8' passes will be of greater diameter han said rod so as to avoid fric tion.

The film frame 17 may be coupled to the machine by any suitable means: my preferred construction for this purpose comprises a,bifurca,ted arm 21 mountedat each end of the plate 14 and the inner ends of these arms straddle the flanges 15. Bolts 22 couple said arms to said flanges 15 and these bolts are held in place by means of nuts 23. The said bolts and nuts or equivalent means can be usedtoregulate the ease of movement of said bifurcated arms 21 in respect of the'flanges 151 24 is any suitable clamp provided at each end with tapered pins 25 mounted in. lugs 26. At one end of the clamp, one of these tapered pins extends into a socket 27 formed in the inner end of a rod 28 mounted in the outer end of one'ofthe arms 21. A coiled spring 29 on said rod betweenthe socket 27 and its associated arm 21 keeps the rod 28 in position so that the socket 27'will be held against its associated tapered pin 25. A stop 30 carried by the rod 28 limits the movement thereof. V

The other end of the clamp 24 is mounted in like manner in its associated arm 21 ex cept that the rod 31 carried by this arm is not spring-held, but is keyed in position by a set screw 32' or equivalent means.

I show a set screw 33 carried by the arm Bl which supports the rod 28 so that the user of the machine desires, he may positively'iock the rod 28 against movement.

The ineans described as exemplary where by the machine is coupled to the film frame 17 permits film frames of different thicknesses to be used and at the same time insure that these frames are held fiat against their supporting surfaces.

Sufficient has been set forth to show that the artist may inspect the surface of his drawing board or stone by raising the film frame 17 upward around the bearings in which the clamp 24'is mounted and bring it back to original position with the assurance that all points of the film will register with the points on the drawing board or stone that they registered with before the film frame was raised. This will enable the reinking of any portion of the surface worked upon with accuracy and without danger of impairing any other portionof the work.

In order to prevent. any 'ten'dency ofthe front plate B to springabovethe back plate A, I provide a clamp dwhi'ch is coup'ied at each end to the plate Abythenuts and screws commonly, designated 6. I desire to make my machine as light as is consistent with accuracy of work and'durabi'lity, and, therefore, the plates A .and B are made quite thin. If these plates be made quite thick, obviously there will be no necessity of using clamp cl or its equivalent;

The preferred means whereb' the supportin member E is coupled to t e drawing board is as follows 34 and 35=arenpper and lower plates between which is clamped the supportin member E. The lower plate 35 is provide with a socket 36 to'receive the movable supporting member E so that the upper surface of this supporting member will be flush with theunders'ide of the plate 34: Screwing' through the plate 34 are set screws 37 which are jammed against the niovable supporting member E to prevent Eeng'itudinaI displacement of said plates. "Screws 38' bind the plates 34 and 35 together as shown clearly in Fig.5.

The lower plate 35 is provided at each end with a socket 39. which sockets extend through holes 40 (see Fig. 5) formed in the upper plate 34. Clamping means such as described must be positioned near each end of the machine and when the machine is to be clamped to a drawing board as illustrated in Fig. 1, the teeth or spurs 41, projecting beyond the inner edge of the lower plate 35, are forced into the drawing board and then the said screws 37 are tightened up, absolutely insuring the firm support of the machine.

.In case it be desired to use my machine in connection with a lithographing stone. I must provide some means whereby the machine is firmly locked to the support or table carrying the stone. My preferred means for this purpose comprises tubular supports 42' substantially of a uniform length and these supports are mounted in the sockets 39. The set screws 43 held in the lower plate 35 of each clamping means maintain the said machine and movable supporting member I) at the required height above the top of the table 44 or other suitable support for the stone (not shown). Screw: are passed down through each of the tubular supports 32 and screw into the table or other support before mentioned, thereby locking the machine and its movable supporting member E firmly in place.

A great advantage derived from the principle of my invention is that the mahine may be attached to the drawing board no matter in what angular position the board is in.

While I have described what I consider to be the best embodiment of my invention, 1 desire it to be understood that the principle may be embodied in different forms, and I desire not to be limited beyond the requirements of the prior art and the terms of my claims.

What I claim as my invention is,

1. A machine of the class described coniprining front and back plates: a movable supporting member to which the said back piatc is firmly coupled; two adjusting screws, each provided with a suitable graduated scale. positioned one at each end of the said plates: alined supporting members carried by said plates with which said adjusting screws are adapted to co-act so that said front plate may be moved toward or away from said back plate the same distance at each end; an adjusting rod provided with a suitable graduated scale. and threaded at one end. and extending at each end through a movable plate positioned" above Said front plate, and means carried by said front plate in which said adjusting rod has hearing and with which the thread of said rod co-acts in order that said movable plate may be shifted longitudinally of said front plate in either direction.

2. A machine of the class described comprising front and back plates; a movable supporting member to which said back plate is firmly coupled; two adjusting screws, each provided with a suitable graduated scale, positioned one at each end of the said plates; alined supporting members carried by said plates with which said adjusting screws are adapted to co'act so that said front plate may be moved toward or away from said back plate the same distance at each end; an adjusting rod provided with a suitable graduated scale, and threaded at one end, and extending at each end through a movable plate positioned above said front plate; means carried by said front plate in which said adjusting rod has bearing and with which the thread of said rod co-acts in order that said movable plate may be shifted longitudinally of said front plate in either direction, and clamping means removably carried by each end of said movable supporting member and adapted to firmly couple said movable supporting member to the body above which said movable supporting member and machine are positioned.

3. A machine of the class described comprising front and back plates; a movable supporting member to which said back plate is firmly coupled; two adjusting screws each provided with a. suitable graduated scale, positioned one at each end of said plates; alined supporting members carried by said plates with which said adjusting screws are adapted to co-act so that said front plate may be moved toward or away from said back plate the same distance at each end; an adjusting rod provided with a suitable graduated scale, and threaded at one end, and extending at each end through a movable plate positioned above said front plate; means carried by said front plate in which said adjusting rod has bearing and with which the thread of said rod co-acts in order that said movable plate may be shifted longitudinally of said front plate in either direction, and clamping means removably carried by each end of said supporting member and adapted to firmly couple said supporting member to the body above which said supporting member and machine are positioned, each comprising upper and lower plates adapted to be clamped to said movable supporting member; a pair of sockets carried by the lower of said plates and extending through holes formed in the upper of said plates; a tubular support adapted to be mounted in each of the said sockets; means whereby said tubular supports are locked in said sockets so as to support said machine and its movable supporting member at the desired height above the surface worked upon, and means operating through said tubular supports whereby the machine and its movable supporting memher are firmly coupled to a support.

a. A machine of the class described comprising front and back plates; a pair of internally-threaded posts carried by said back plate and positioned one at each end thereof; a pair of bearing posts carried by said front plate and positioned one at each end thereof and each in alinement with its associated internally-threaded post; an adjustable screw mounted in each of the said threaded posts and extending through the said bearing posts; a nut carried by the inner end of each of said adjustable screws and each provided with a suitable graduated scale; means whereby said adjustable screws are rotatably mounted in said bearing posts and held against longitudinal movement therein so that when said adjusting screws are turned, the said plates may be separated the same distance at both ends; an adjusting rod threaded at one end; a pair of bearing blocks carried by said front plate through which said adjusting rod extends and with one of which it has threaded engagement; a movable plate through which each end of said adjusting rod extends; a nut provided with a graduated scale carried by said adjusting rod and co-acting with means carried by the other end of said rod and with said movable plate whereby said movable plate may be shifted longitudinally of said front plate in either direction, and a supporting member whereby said back plate is clamped in position.

5. In a machine of the class described, in combination a back plate provided at its rear side with a flange depending therebelow; a grooved movable supporting member to which said back plate is firmly coupled and against which said flange abuts; a pair of internally-threaded supporting members positioned one at each end of said back plate and each with its vertical axis in alinement with the longitudinal center of the groove formed in said movable supporting member; means coupling said internally-threaded supporting members to said back plate and depending therebelow and into the said roove; a front plate; a pair of alined bearing members carried by said front plate one at each end thereof; adjusting screws threaded through said internally-threaded supporting members and having bearing at their forwards ends in the bearing members carried by said front plate; means whereby the forward ends of said adjusting screws are allowed rotary movement in said bearing members and held against longitudinal movement therein, the whole designed to cooperate as set forth.

6. In a machine of the class described, in combination a base plate; a second plate ex tending longitudinally of said base plate and operating above the same and provided at each end with an upturned flange; a pair of bearing blocks carried by said base plate and overhanging said second-mentioned plate and having clearance therewith; an adjusting rod mounted in said bearing blocks and provided with a thread at one end for engagement with a threaded hole in one of said bearing blocks; the said adjustin rod projecting through the said flanges; nger pieces associated with each end of said adjusting rod and operating against the outer side of each of the said flanges, one of said finger pieces being provided with a graduated scale so that said second-mentioned plate may be shifted longitudinally in either direction, and set screws carried by the forward portions of said bearing blocks which overhang said second-mentioned plate and are designed to rest in a groove formed lhngitudinally of said second-mentioned plate, as

set forth and for the purpose specified.

7. In a shading machine, in combination a supporting memb'er; clamping means mounted at each end thereof comprising upper and lower plates; the said lower plate being provided with a socket to receive said supporting member and said upper plate being provided with holes; sockets carried by said lower plate and projecting through the holes formed in said upper plate; means whereby said plates are removably coupled together; means whereby said clamping means are clamped to said supporting memher in the desired position; tubular supports mounted in each of the said sockets to regulate the height of the supporting member above the surface operated upon; means whereby said clamping means are locked to said tubular supports, and means extending through said tubular supports whereby said supporting member may be firmly coupled to a table top.

WILLIAM HENRY MARGETTS. 

